Switching rate monitoring and control

Apparatus comprising:

• a differentiator circuit including a reference input, a resistor, and capacitor, the capacitor having first and second terminals, the references input coupled through the resistor to the first terminal, and the second terminal adapted to be coupled to an output terminal of a switch;
• a peak detector circuit having a detector input and a detector output, the detector input coupled to the first terminal;
• an amplifier having an amplifier input and first and second amplifier outputs, the amplifier input coupled to the detector output;
• a comparator having a comparator output and first and second comparator inputs, the first and second comparator inputs respectively coupled to the first and second amplifier outputs, in which the comparator output is responsive to a comparison by the comparator of:
• the first comparator input to a positive reference value;
• the second comparator input to a negative high side reference value;
• and the second comparator input to a negative low side reference value;
• and
• a digital controller haivng a controller input and a controller output, the controller input coupled to the comparator output, the controller output adapted to be coupled to a control terminal of the switch, and the digital controller configured to adjust the controller output responsive to the controller input.

A method, comprising:

• receiving, by a differentiator circuit, a voltage from a switch;
• deriving a differentiated voltage from the voltage;
• detecting a peak value of the differentiated voltage;
• responsive to the peak value of the differentiated voltage being greater than a first threshold voltage, adjusting a control signal to the switch;
• amplifying the detected peak voltage to generate a first amplifier output signal and a second amplifier output signal;
• and
• comparing the first amplifier output signal and the second amplifier output signal to a reference voltage, and generating a high side comparator output signal and a low side comparator output signal responsive to the comparison.